fix: upgrade core-js from 3.8.2 to 3.8.3

Snyk has created this PR to upgrade core-js from 3.8.2 to 3.8.3.

See this package in npm:
https://www.npmjs.com/package/core-js

See this project in Snyk:
https://app.snyk.io/org/revjtanton/project/566b77b1-82a7-41d4-a6c9-d206ddcdb918?utm_source=github&utm_medium=upgrade-pr

Author: snyk-bot

package-lock.json

@@ -16,7 +16,7 @@
     "babel-runtime": "6.26.0",
     "bootstrap": "^4.5.3",
     "bootstrap-vue": "^2.21.2",
-    "core-js": "^3.8.2",
+    "core-js": "^3.8.3",
     "dotenv": "8.2.0",
     "eslint-plugin-jest": "^24.1.3",
     "helmet": "3.23.3",